Airbag apparatus

ABSTRACT

To provide an airbag apparatus in which the gas generator can be mounted quite easily to the gas generator mounting portion of the airbag without causing gas leakage at all. A curtain-like airbag having an elongated cylindrical gas generator mounting portion is provided on the upper side surface of the cabin for protecting the passenger of the automotive vehicle. A gas generator insertion port is provided at both ends of the gas generator mounting portion. A gas generator is inserted into the gas generator insertion port, and fastened tightly with a fastener from the outer periphery of the gas generator insertion port. The gas generator is constructed in such a manner that a casing is fitted on a hybrid inflator concentrically with a cylinder and a gas exhaust port is provided on the side peripheral surface of the casing.

BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT

[0001] The present invention relates to an airbag apparatus forprotecting passengers in the high-speed movable body such as automotivevehicles in case of collision, and more specifically, an air bagapparatus in which the connecting portion between the airbag and the gasgenerator is improved. Especially, the present invention relates to anairbag apparatus suitable for applying to the airbag that deploys like acurtain along the side surface of the cabin of the automotive vehicle.

[0002] This type of protection bag for the head of the passenger in theautomotive vehicle is disclosed in W096/26087,and specifically shown inFIG. 1 and FIG. 9 therein. In this known bag, the air chamber comprisesa duct portion extending along the upper edge of the bag from the end ofthe bag facing toward the front of the vehicle (front end) to the endfacing toward the back of the vehicle (rear end), and a number of cellsextending continuously downward from the duct portion. The gas generatoris connected to the duct portion on the side facing toward the rear ofthe vehicle. The gas generator generates gas upon collision of thevehicle, and gas flows into the duct portion from the side facing towardthe rear of the vehicle and deploys the cells from the cell at the rearend in a sequential order. Therefore, the cell on the front end isdeployed significantly behind the cell on the rear side.

[0003] As a protection bag for the head of the passenger of theautomotive vehicle in which the time difference of the deploymentbetween the respective portions of the bag is small and is rapidlydeployed as a whole, the one which is provided with a gas inlet port atthe center of the bag when viewed in the fore-and-aft direction of thevehicle is proposed in Japanese Patent Application PublicationNo.10-291457

[0004]FIG. 5 is a bag shown in the same publication, in which FIG. 5(a)is a perspective view showing a state in which gas in introduced in thebag and deployed, and FIG. 5(b) and FIG. 5(c) are cross sectional viewstaken along the lines 5(b)-5(b) and 5(c)-5(c) of FIG. 5(a) respectively.

[0005] The bag 10 is provided with a plurality of longitudinal airchambers 12 formed by overlapping two almost fan-shaped sheets andjoining the entire peripheral margin and prescribed positions in thevertical direction. The upper portions of the air chambers 12 are incommunication with the upper air chamber 14. An opening 16 for supplyinggas into the upper air chamber 14 is provided at the longitudinal centerthereof.

[0006] In the bag 10 constructed in a manner described above, gas issupplied into the upper air chamber 14 from the opening 16 when theautomotive vehicle crashes or rolls over. The supplied gas deploys theupper air chamber 14 and the longitudinal air chambers 12, and thus thebag 10 is deployed along the door window or the like.

[0007] In the Japanese Patent Application Publication No.10-291457, howthe gas generator is connected to the gas inlet port 16 is notdisclosed.

[0008] It is an object of the present invention to provide an airbagapparatus in which the gas generator is mounted to the gas inlet porteasily and without causing gas leakage at all, and in which the airbagcan be deployed smoothly as a whole.

[0009] Further objects and advantages of the invention will be apparentfrom the following description of the invention.

SUMMARY OF THE INVENTION

[0010] The airbag apparatus of the present invention is an airbagapparatus comprising an airbag having a gas inlet port, and a gasgenerator for generating gas for deploying the airbag, characterized inthat the gas generator has a long cylindrical shape with a gas exhaustport on its side peripheral surface, in that the airbag has a gasgenerator mounting portion continuing to the gas inlet port and the gasgenerator mounting portion is provided with a pair of gas generatorinsertion ports at a prescribed distance, in that the gas exhaust portof the gas generator is arranged in the gas generator mounting portionin such a manner that both ends are inserted into the respective gasgenerator inserting ports, and in that the gas generator insertion portis fastened tightly from the outside by an annular fastener.

[0011] In such an airbag apparatus, the gas generator can easily bemounted by inserting the same into the gas generator insertion port andfastening tightly by an annular fastener, and no gas leakage happens atall.

[0012] Gas generated from the gas generator is supplied from the gasinlet port into the entire portion of the interior of the airbagsmoothly, and thus the airbag is deployed quickly as a whole.

[0013] The pair of gas generator insertion ports are preferably formedinto a cylindrical shape. The fastener is preferably formed of metal,and constructed to fasten tightly by caulking.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]FIG. 1 is a cross sectional view of the upper center of the airbagapparatus according to an embodiment;

[0015]FIG. 2 is a perspective view of the fastener;

[0016]FIG. 3 is a perspective view of the fastener with the diameterreduced;

[0017]FIG. 4 is a cross sectional view of the gas generator; and

[0018]FIG. 5 is a block diagram showing a conventional airbag.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0019] Referring now to the drawings, an embodiment of the presentinvention will be described.

[0020]FIG. 1 is a block diagram showing the upper portion of thelongitudinal midsection of the airbag apparatus according to thisembodiment; FIGS. 2 and 3 are perspective views of the fastener; andFIG. 4 is a cross sectional view of the gas generator.

[0021] As shown in FIG. 1, a curtain-like air bag 30 having an elongatedcylindrical gas generator mounting portion 32 is mounted on the upperside surface in the cabin (for example, along the roof side rail) forprotecting the passenger in the automotive vehicle. The mounting portion32 is provided near the longitudinal midsection (when viewed in thefore-and-aft direction) of the airbag 30.

[0022] The cylindrical gas generator mounting portion 32 is providedwith gas generator insertion ports 34 at both ends thereof.

[0023] The gas generator 20 is inserted through the gas generatorinsertion port 34 and fastened tightly with fasteners 22 from the outerperipheral side of the gas generator insertion ports 34.

[0024] The fastener 22 is formed of metal, and has a looped projectingportion 22 a as shown in FIG. 2. By caulking and deforming theprojecting portion 22 a as shown in FIG. 3, the fastener 22 is decreasedin diameter and tightly fastens the gas generator insertion port 34 fromthe outside. Accordingly, the gas generator 20 is quite easily andstably fixed into the gas generator insertion port 34, and gas leakagefrom the gas generator insertion port 34 is prevented.

[0025] Referring now to FIG. 4, the structure of the gas generator 20will be described. The gas generator 20 is constructed of a hybridinflator 40 stored in a cylindrical casing 54.

[0026] The hybrid inflator 40 is constructed in such a manner thatpropellant and high-pressure gas are filled in the pressure resistantcylinder 42, and an initiator 44 is mounted at one end of the cylinder42, and a gas exhaust port 48 is provided on the tip surface of the endcap 46 mounted at the other end.

[0027] A cylindrical cup shaped inflator cap 50 is fitted on the end cap46, and gas exhaust ports 52 are provided on the side peripheral surfaceof the inflator cap 50.

[0028] The cylindrical casing 54 is fitted on the hybrid inflator 40concentrically with the cylinder 42, and gas exhaust ports 56 areprovided on the side peripheral surface of the casing 54.

[0029] A clearance is defined between the inner peripheral surface ofthe casing 54 and the outer peripheral surface of the cylinder 42. Thisclearance is a gas passage 58. The inflator cap 50 abuts against the endportion 60 of the casing 54 shown at the left end of the figure.

[0030] The gas generator 20 is mounted to the gas generator mountingportion 32 in such a manner that the gas exhaust ports 56 are disposedin the gas generator mounting portion 32.

[0031] When the automotive vehicle crushes on its side, the initiator 44is energized, and propellant in the cylinder 42 reacts, and gasgenerated by the reaction discharges through the gas exhaust port 48together with high-pressure gas stored in the cylinder 42. The exhaustgas discharges from the gas exhaust port 52 of the inflator cap 50 inthe radial direction, passes through the gas passage 58, and is blownout from the gas exhaust port 56. This gas deploys the airbag 30. Theairbag 30 deploys quite smoothly as a whole because the gas dischargedfrom the gas generator 20 is directly injected into the airbag 30, andthe gas inlet port is provided near the longitudinal midsection of theairbag 30.

[0032] As described above, according to the airbag apparatus of thepresent invention, the gas generator can be mounted quite easily to thegas generator mounting portion of the airbag without causing gas leakageat all. According to the present invention, it is also possible toconstruct the airbag so as to be deployed smoothly as a whole.

[0033] While the invention has been explained with referenceto thespecific embodiment of the invention, the explanation isillustrative andthe invention is limited only the appended claims.

What is claimed is:
 1. A vehicle deployable airbag system comprising: aninflatable airbag having a gas inlet port and a gas generator mountingportion continuing to said gas inlet port, said mounting portionincluding a pair of gas generator inserting ports spaced a predetermineddistance from one another, an elongated gas generator for generating gasfor deploying said airbag, said gas generator having opposed ends and anexhaust port on its peripheral surface intermediate said ends, said gasgenerator being mounted in said mounting portion with said opposed endsinserted one into each of said inserting ports, and annular fasteningmeans tightly fastening each said insertion port to said gas generatorfrom the outside.
 2. The airbag system as defined in claim 1, whereinsaid pair of gas generator inserting ports is in the form of an openended cylinder.
 3. The airbag system as defined inclaim 1, wherein saidfastening means is in the form of a metal clamp and is fastened tightlyby press-fitting.
 4. The airbag system as defined inc laim 1, whereinsaid air bag is mounted along a side surface of a vehicle cabin and isdeployed in a form of a curtain, said gas inlet port being disposed atan upper mid portion of said airbag when viewed in a fore-and-aftdirection of the vehicle.
 5. The airbag system as defined in claim 4,wherein said fastening means is in the form of a metal clamp and isfastened tightly by press-fitting.
 6. The airbag system as defined inclaim 1, wherein said airbag is mounted along a side surface of avehicle cabin and is deployed like a curtain, said gas inlet port beingdisposed at an upper mid portion of said airbag when viewed in thefore-and-aft direction of the vehicle.